As the world population increases and the consumption of animal protein increases, the need for supplementary vegetable sources of protein increases in direct proportion. The demand for less expensive protein has expanded greatly because the overall protein demand and ever-increasing production costs have driven the cost of animal protein to new record levels.
Traditional meat products have characteristic flavors, textures and overall appearances which are still in demand. The most effective and acceptable way to reach the increasing protein market with a vegetable protein product is by combining the vegetable protein product with conventional animal protein products such as frankfurter sausages, braunschweiger, and other prepared meats, or by creating a meat analog which has all the desired organoleptic appeal.
Such meat analogs simulate meat products with a total vegetable product having the texture, flavor and appearance of the meat product, such as hamburger, chicken, turkey, beef and the like. The flavors must be added to the basic vegetable protein product, and product texture is obtained by extrusion, spinning, precipitation or other means. Quality control to ensure continued excellent flavor, texture and appearance is essential, because one off-quality release can damage the product's reputation in a lasting way.
The combination of vegetable protein with meat products utilizes the natural flavor of the meat product. The vegetable protein is added to increase the total useful protein of a given amount of meat product at a reduced cost to the ultimate consumer who wants to pay less, but without sacrificing natural meat flavor, texture and appearance.
The vegetable products which are combined with such meat products should therefore be as bland in flavor as possible, and should not counteract the normal texture, moisture level and appearance of the meat products with which they are combined. Many vegetable protein materials presently available have been combined with meat products, with varying levels of success. In some cases, the meat-vegetable protein product absorbs moisture at a nonuniform rate, resulting in a mushy, uneven and unsightly texture. Some vegetable protein products have been processed at high temperatures, and have a characteristic "toasted" taste which adversely affects the meat flavor. Other vegetable protein products have a too high, or too low, protein solubility index compared to the meat product, and the combination product has an undesirable texture.
The object of such meat-vegetable protein combinations should be to obtain a protein product as good, or better than, the meat product in nutritional level, in general appearance, texture and flavor. Soy protein concentrates, in particular, tend to have a somewhat "beany" flavor, although they have excellent protein content. A bland soy protein concentrate which does not interfere with the meat product texture and flavor is, therefore, a most desirable product which will enjoy a rapidly expanding market if present demands continue. An economical and reliable method for making such a bland protein concentrate having a consistent nitrogen solubility index and water absorption properties within a desired range has been the goal of applicants' development efforts. Bland soy protein concentrate is also desirable for making meat analogs, snack foods, cereals, baked products and liquid protein foods, such as calf milk replacer and liquid protein supplements for infants.